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To identify the ability of the isolated strains to destroy organic waste, their preliminary selection was carried out by cultivation on manure agar for 14 days. It was found that the most intensive use of organic residues in laboratory models of the medium was possessed by strains No. 1,3,4,5,6,7,11,12,14,15, 21, 32 Lactococcus, Trichoderma, Sacharomyces, Candida, Pseudomonas, Lactobacillus. They were used for further experiments. All the studied microorganisms have amylolytic activity: strains No. 1, 6, 8, 9 and 10 hydrolyze starch by 100%; strain No. 4 - by 94.4%; No. 5 - by 84.8%; No. 7 and 12 - by 92.3%; strains No. 2, 3 and 11 – by 83.3 and 47.2%. The most pronounced proteolytic activity is shown by strains № 2, 3, 4, 5, 7, 11 the width of the illumination zone ranged from 1 to 1.2 cm. Moderately pronounced proteolytic properties were noted in strains No. 6 and 8, the width of the enlightenment zone is from 0.4 to 0.5 cm. Strains No. 1, 9, 10 and 12 showed weak proteolytic properties. The zone of enlightenment of the medium during the growth of these microorganisms is practically absent. Of the isolated isolates, practically all microorganisms did not possess phytotoxic properties. Based on the conducted research, the selected strains of microorganisms will be used for possible biodegradation of organic waste in agriculture and for the greening of territories. [ABSTRACT FROM AUTHOR]

A numerical simulation of a supersonic (M∞ = 7) flow around a cylinder with a front gas-permeable porous insert at a zero angle of attack was carried out using three-dimensional skeleton models of a highly porous cellular material made of non-intersecting hard spheres with a regular and chaotic arrangement of pores. A comparative analysis of these skeleton models with different spatial arrangement and pore size showed a weak influence of the structure of skeleton models on the resistance of a cylinder with a front gas-permeable insert. The computed data of the drag coefficient are compared with the results of tube experiments. [ABSTRACT FROM AUTHOR]

The paper presents the results of numerical and experimental modeling of a supersonic (M∞ = 7) flow around a cylinder with a front gas-permeable porous insert at different angles of attack. A three-dimensional skeletal ring model of a highly porous cellular material has been constructed and implemented for the numerical simulation of the problem. Experimental studies were carried out in a T-327 wind tunnel of the ITAM SB RAS. The calculated data of the aerodynamic drag coefficients are compared with the results of experiments. [ABSTRACT FROM AUTHOR]

The problem of supersonic (M∞ = 7) flow around a hollow cylinder with end gas-permeable porous inserts located at a zero angle of attack is solved experimentally and numerically. In experiments in the wind tunnel, the end inserts are heated by an electric glow discharge to regulate the flow rate of air directed to the bottom region. Measurements of the air temperature in the bottom area and the aerodynamic drag of the model are performed. Numerical simulation of the problem was carried out by the ANSYS Fluent package using a ring skeleton model of a highly porous cellular material. It is shown that the heating of the end gas-permeable inserts leads to an increase in the air temperature in the bottom region, as a consequence to a decrease in the bottom pressure and an increase in the aerodynamic drag of the model. [ABSTRACT FROM AUTHOR]

To ensure the possibility of designing modern spacecraft power supply systems based on Stirling engines, computational tools are needed to simulate their work in a wide range of modes, to take into account the influence of the subsystems on each other and on the final characteristics of the propulsion. This paper creates a thermodynamic model of a Stirling free-piston engine, taking into account the hydraulic losses in the elements of the thermal circuit. The model is based on an isothermal approximation. The model was implemented in Matlab. The system of differential equations was integrated using the 4-th order Runge-Kutta method. An objectives database has been prepared for the validation of a mathematical model in the power range from 1 to 50 kW. The article presents the basic equations for the mathematical model and computational schemes, as well as some results of numerical simulation and validation results. The deviations obtained between the calculated and experimental data on the magnitude of the amplitudes and phases of the movement of the pistons do not exceed 8%, which is a fairly good result for models of this class. The model developed can be used in the early stages of spacecraft design for a preliminary assessment of the main indicators of the Stirling engine. [ABSTRACT FROM AUTHOR]

To be able to design modern power plants of spacecraft built based on Stirling engines, it is necessary to use calculation tools to simulate their operation in a wide range of modes, to take into consideration the influence of subsystems on each other and the final characteristics of the plant (power plan”). As part of the work, a thermodynamic model of an external thermal circuit was created, consisting of heat pipes, heat exchangers and radiator panels. A mathematical model of the Stirling engine of the first order has been also implemented. The developed models were independently debugged and then integrated into a single model of the power plant. The model is implemented in an open simulation environment of xcos/scilab. Numerical experiments were carried out to study the dynamics of the heating of the contour elements and the effect of the non-stationary thermal state on the engine performance. The article presents the basic equations for the thermal circuit and the design schemes, as well as some results of numerical simulation, including the dynamics of changes in the indicator diagram of the engine when the external thermal circuit is heated. The developed model can be used in the early stages of spacecraft design for a preliminary assessment of the main indicators of the power plant, its dimensions and thermal loads. [ABSTRACT FROM AUTHOR]